GtkMapListModel

GtkMapListModel — A list model that transforms its items

Properties

gboolean has-map Read
GListModel * model Read / Write / Construct Only

Types and Values

Object Hierarchy

    GObject
    ╰── GtkMapListModel

Implemented Interfaces

GtkMapListModel implements GListModel.

Includes

#include <gtk/gtk.h>

Description

GtkMapListModel is a list model that takes a list model and maps the items in that model to different items according to a GtkMapListModelMapFunc.

Example: Create a list of GtkEventControllers

static gpointer
map_to_controllers (gpointer widget,
                    gpointer data)
 {
  gpointer result = gtk_widget_observe_controllers (widget);
  g_object_unref (widget);
  return result;
 }

widgets = gtk_widget_observe_children (widget);

controllers = gtk_map_list_model_new (G_TYPE_LIST_MODEL,
                                      widgets,
                                      map_to_controllers,
                                      NULL, NULL);

model = gtk_flatten_list_model_new (GTK_TYPE_EVENT_CONTROLLER,
                                    controllers);

GtkMapListModel will attempt to discard the mapped objects as soon as they are no longer needed and recreate them if necessary.

Functions

GtkMapListModelMapFunc ()

gpointer
(*GtkMapListModelMapFunc) (gpointer item,
                           gpointer user_data);

User function that is called to map an item of the original model to an item expected by the map model.

The returned items must conform to the item type of the model they are used with.

Parameters

item

The item to map.

[type GObject][transfer full]

user_data

user data

Returns

The item to map to. This function may not return NULL.

[type GObject][transfer full]

gtk_map_list_model_new ()

GtkMapListModel *
gtk_map_list_model_new (GListModel *model,
                        GtkMapListModelMapFunc map_func,
                        gpointer user_data,
                        GDestroyNotify user_destroy);

Creates a new GtkMapListModel for the given arguments.

Parameters

model

The model to map or NULL for none.

[transfer full][allow-none]

map_func

map function or NULL to not map items.

[allow-none]

user_data

user data passed to map_func .

[closure]

user_destroy

destroy notifier for user_data

Returns

a new GtkMapListModel

gtk_map_list_model_set_map_func ()

void
gtk_map_list_model_set_map_func (GtkMapListModel *self,
                                 GtkMapListModelMapFunc map_func,
                                 gpointer user_data,
                                 GDestroyNotify user_destroy);

Sets the function used to map items. The function will be called whenever an item needs to be mapped and must return the item to use for the given input item.

Note that GtkMapListModel may call this function multiple times on the same item, because it may delete items it doesn't need anymore.

GTK makes no effort to ensure that map_func conforms to the item type of self . It assumes that the caller knows what they are doing and the map function returns items of the appropriate type.

Parameters

self

a GtkMapListModel

map_func

map function or NULL to not map items.

[allow-none]

user_data

user data passed to map_func .

[closure]

user_destroy

destroy notifier for user_data

gtk_map_list_model_set_model ()

void
gtk_map_list_model_set_model (GtkMapListModel *self,
                              GListModel *model);

Sets the model to be mapped.

GTK makes no effort to ensure that model conforms to the item type expected by the map function. It assumes that the caller knows what they are doing and have set up an appropriate map function.

Parameters

self

a GtkMapListModel

model

The model to be mapped.

[allow-none]

gtk_map_list_model_get_model ()

GListModel *
gtk_map_list_model_get_model (GtkMapListModel *self);

Gets the model that is currently being mapped or NULL if none.

Parameters

Returns

The model that gets mapped.

[nullable][transfer none]

gtk_map_list_model_has_map ()

gboolean
gtk_map_list_model_has_map (GtkMapListModel *self);

Checks if a map function is currently set on self

Parameters

Returns

TRUE if a map function is set

Types and Values

GtkMapListModel

typedef struct _GtkMapListModel GtkMapListModel;

Property Details

The “has-map” property

  “has-map”                  gboolean

If a map is set for this model

Owner: GtkMapListModel

Flags: Read

Default value: FALSE

The “model” property

  “model”                    GListModel *

The model being mapped

Owner: GtkMapListModel

Flags: Read / Write / Construct Only

See Also

GListModel

© 2005–2020 The GNOME Project
Licensed under the GNU Lesser General Public License version 2.1 or later.
https://developer.gnome.org/gtk4/4.0/GtkMapListModel.html